Open AccessEffects of Raman pump power distribution on output spectrum in a multi-wavelength BRFL
Author(s) -
Ghazaleh Mamdoohi,
A. R. Sarmani,
M. H. Abu Bakar,
Mohd Adzir Mahdi
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.025570
Subject(s) - optics , lasing threshold , materials science , laser , wavelength , raman spectroscopy , brillouin scattering , bandwidth (computing) , fiber laser , raman amplification , raman scattering , optoelectronics , physics , telecommunications , computer science
This paper aims to investigate changes in multi-wavelength Brillouin-Raman fiber laser (MBRFL) spectra characteristics that are influenced by variation of Raman pump power distribution along the two fiber-entry points. This is carried out by incorporating a Raman pump source with a set of couplers with various ratios. In this arrangement, the optimization of pumping ratio is properly carried out to achieve high number of lasing lines with 20 GHz spacing which yield the highest peak power discrepancy between odd- and even-order lasing lines and an excellent Stokes optical signal-to-noise ratio (S-OSNR). Employment of 50/50 coupler offers 212 flat amplitude channels with an average 27.5 dB S-OSNR and -10 dBm Stokes peak power when the Brillouin pump wavelength is set at 1543 nm. Achievements such flat and wide bandwidth MBRFL spectrum with 20 GHz spacing and excellent S-OSNR utilizing just a single pump source is significant in terms of simplicity and flexibility.